Professional wrestler Mike Shaw, most famous for his roles as Norman the Lunatic in World Championship Wrestling and Bastion Booger in the then-World Wrestling Federation, had a heart attack on Saturday and died at the age of 53.

Shaw was trained by wrestling legend Killer Kowalski, and got his first break in Calgary’s Stampede Wrestling as Makhan Singh, a rival of Owen Hart and Brian Pillman. He competed in WCW in the late 1980s as Norman the Lunatic, an escaped mental patient who feuded with Kevin Sullivan and challenged Ric Flair for the World Heavyweight Championship.

Shaw’s original character in the WWF was Friar Ferguson, the “mad monk,” but quickly dropped the persona following negative feedback from the Catholic Church of New York. He was turned into the grotesque Bastion Booger, perhaps his most famous (and infamous) role.

Shaw’s last televised appearance was a cameo on the WWE Raw 15th anniversary special. He is survived by his wife Kelly and their two children, son Joshua and daughter Amanda.